I use Emerson as everyday carry knives. I have other knives which work well for that purpose, too. My favorite is a Chris Reeve Sebenza...but frankly, it's too expensive to carry daily, and too nice to ruin with utility use.
I generally carry a couple of pocket knives: an Emerson, and a spyderco military or paramilitary. Both get used a lot. I've got a wall of one gun safe covered in knives, including a number of Emersons; many used, some not used at all, some used on a regular basis and maintained for that purpose. I've honestly never had an issue with the edge on those knives, save or a couple of used ones that arrived in the mail with rolled edges or otherwise in need of some help.
I don't ascribe to the popular "tactical" or "tacticool" rubbish. It's a knife. Much like a firearm, it's not anything until someone picks it up and uses it. If one uses it strategically, then I suppose it's a strategic knife. If one uses it tactically, then I suppose it's a tactical knife. In the end, it's just a knife...not a tactical knife, not a strategic knife...it's just a knife And a pocket knife at that.
Any time a knife needs to be used defensively (or offensively, for that matter), the environment has deteriorated to a rather dire situation. One is in bad shape if one has fallen back to depending on one's pocket knife. Having been there, however, for both defense and for other needs, I recognize the wisdom of carrying a dependable tool in one's pocket. I have a long background as a mechanic, and came to recognize long ago the advantage of buying good tools.
My first Emerson was a mini-commander, and I knew as soon as I inspected it out of the box that it was a keeper, and would be with me a long time. Not too many knives strike me that way, but the Emerson products have, as have a few of the Spyderco products. Neither are high dollar custom knives, and neither one are particularly pretty...they're working knives for common folk like myself. I don't expect the knife to stay sharp forever; that's what maintenance is for. I've not noticed that the Emerson knives dull any faster than any other, all else being equal, but I have noticed that when kept sharp, they work extremely effectively.
My sole complaint wouldn't be the sharpness or lack thereof, but rather the nature of the grind...which as described above has been tackled for now. This really comes down to a function of one's intended use of the knife. In my case, I find myself slicing more often than I do using it defensively, though I do want a knife that can fill that role without hesitation. The regrinds seem to fill that need.